Ureidophenyl phenyl carbamates

ABSTRACT

Substituted ureidophenyl phenyl carbamates and the use of said compounds for controlling unwanted plant growth.

United States Patent [72] Inventors Hermann Windel Frankenthal, Pfalz; Adolf Fischer, Mutterstadt, Pfalz, both of Germany [21 Appl. No. 730,893

[22] Filed May 21, 1968 [45] Patented Nov. 23, 197 l [73] Assignee Badische Anilin- & Soda-Fabrik Aktiengesellschaft Ludwigshalen, Rhine, Germany [32] Priority May 31, 1967 [33] Germany [54] UREIDOPHENYL PHENYL CARBAMATES 2 Claims, No Drawings [52] US. Cl 260/471 C, 71/l 11,260/468 C, 260/553 C [5 1] Int. Cl .l ..C07c 125/06 [50] Field of Search 260/468 C, 47l C [56] References Cited UNITED STATES PATENTS 3,404,975 10/1968 Wilson etal. 260/471 Primary Examiner-Charles B. Parker Assistant Examiner-L. Arnold Thaxton Anorney-Marzall, Johnston, Cook & Root ABSTRACT: Substituted ureidophenyl phenyl carbamates and the use of said compounds for controlling unwanted plant growth.

good herbicidal properties. Another object of the invention is i to provide a method for controlling unwanted plant growth with substituted ureidophenyl phenyl carbamates, especially for controlling unwanted plant growth without damaging the crop plants.

These and other objects of the invention are achieved with substituted ureidophenyl phenyl carbamates having the formula in which R denotes a phenyl radical which may be substituted by halogen, nitro, methoxy, carboxy, lower alkyl or lower haloalkyl, or a cycloaliphatic radical having three to eight carbon atoms in the cycloaliphatic ring which may be substituted by halogen or alkyl and R R, R and R denote hydrogen, methoxy, a phenyl radical, or a saturated or unsaturated aliphatic radical which may be substituted by halogen. Compounds in which R denotes l-butynyl-(3) also exhibit good action.

The compounds according to the invention may be prepared by reacting m-aminophenol with the appropriate carbamyl halides, preferably the chlorides, if desired in the presence of agents binding hydrogen halide, or with the appropriate isocyanates to the corresponding ureas which are substituted on the phenyl radical in m-position by the hydroxy group. These ureas are converted with the appropriate carbamyl halide, preferably the chloride, if necessary in the presence of agents binding hydrogen halide, or with the appropriate isocyanate to form carbamic esters.

The following experiments (parts by weight) will illustrate the preparation of the compounds according to the invention.

EXPERIMENT 1 10.8 parts of dimethylcarbamyl chloride is slowly added to a suspension of 2 l .8 parts of m-aminophenol in 50 parts of dioxane while stirring at 20 to 40 C., the mixture is stirred for 8 hours at room temperature (20 C.) and the dioxane is distilled 00. The residue is washed with water and N-(mhydroxyphenyl)-N',N-dimethylurea is obtained in a purity which is adequate for further processing (m.p. 183 to 184 C.).

If methylcarbamyl chloride is used instead of dimethylcarbamyl chloride. N-(m-hydroxyphenyl)-N'-methylurea is obtained.

1f phenylcarbamyl chloride is used instead of dimethylcarbamyl chloride, N-(m-hydroxyphenyl)-N-phenylurea is obtained.

9.3 parts of N-(m-hydroxyphenyl)-N'.N-dimethylurea, 10 parts of pyridine and 7.7 parts of p-chlorophenyl isocyanate are kept in an autoclave for 8 hours at 60 C. The mixture is then treated with water and the residue is filtered off and dried. The m-(3,3-dimethy1ureido)-phenyl N-p-chlorophenyl carbamate thus obtained has a melting point of 1 12 to 1 14 C. and the following structural formula lim- EXPERIMENT 2 A solution of six parts by weight of phenyl isocyanate in 50 parts of benzene is added at 20 to 30 C. to a suspension of 9.3 parts of N-(m-hydroxyphenyl)-N',N'-dimethylurea and 0.5 part of pyridine in parts of benzene. The whole is stirred for 6 hours at 60 C. and the residue if filtered off. The m-(3,3-dimethylureido)-phenyl phenyl carbamate has a melting point of 180 to 182 C.

if N -(m-hydroxyphenyl)-N'-methy1urea or N-( m-hydroxyphenyl)-N'-phenylurea is used instead of N-(m-hydroxyphenyl)-N',N'-dimethylurea, 3-methy1ureido or 3-phenylureido phenyl ester derivatives are obtained.

The agents for regulating plant growth according to this invention may be used as solutions, emulsions, suspensions or dusts. The form of application depends entirely on the purpose for which the agents are being used; in any case it should ensure a fine distribution of the active ingredient.

For the preparation of solutions to be sprayed direct, mineral oil fractions with medium to high-boiling points such as kerosene or diesel oil, coal tar oils and oils of vegetable and animal origin, cyclic hydrocarbons, such as tetrahydronaphthalene, and alkylated naphthalenes are suitable.

Aqueous formulations may be prepared from emulsion concentrates, pastes or wettable powders by adding water. To prepare emulsions the ingredients as such or dissolved in a solvent may be homogenized in water by means of wetting or dispersing agents. Concentrates which are suitable for dilution with water may be prepared from active ingredient, emulsifying or dispersing agent and possibly solvent. The agents may also be applied in granulated form.

insecticides, fungicides, bactericides and other herbicides may be added to the agents or the latter may be mixed with fertilizers.

Dusts may be prepared by mixing or grinding the active ingredients with a solid carrier.

The following examples illustrate the application of the agents according to the invention.

EXAMPLE 1 The plants barley (Hordeum vulgare), wheat (Triticum vulgare), lndian corn (Zea mays), beet (Beta vulgaris), wild mustard (Sinapis arvensis), common chickweed (Stellaria media), white goosefoot (Chenopodium album), small nettle (Urtica urens) and barnyard grass (Panicum crus galli) were treated at a growth height of 2 to 12 cm. with 2 kg. per hectare of each of the following active ingredients:

m-( 3,3-dimethylureido)-phenyl N-p-chlorophenyl carbamate 1 methyl N-3,4-dichlorophenyl carbamate ll m-(3,3-dimethylureido)-phenyl N-3,4-dichlorophenyl carbamate lll m-(3,3-dimethylureido)-phenyl N-3,4-dimethylphenyl carbamate l V m.p. 102 to 104 C. m-( 3,3-dimethylureido)-phenyl N-methylphenyl carbamate v m.p. 164 to 166 C. m-( 3,3-dimethylureido)-phenyl N-3-methylphenyl carbamate Vl m-(3,3-dimethylureido)-phenyl N-4-methoxyphenyl carbamate Vll mp. 138 to 140 C. m-(3,3-dimethylureido)-phenyl N-3-methoxyphenyl carbamate Vlll m.p. 148 to 150 C. m-(3,3-diethylureido)-phenyl N-3-m-chlorophenyl carbamate m-( 3-methylureido)-phenyl N-3-m-chlorophenyl carbamate X i m-( 3-methylureido )-phenyl N-3,4-dichlorophenyl carbamate m-(3-methylureido)-phenyl N-2-chlorophenyl X11 5 mp. 148 to 150 C. each dispersed in 500 liters of water per hectare. After 2 to 3 m-(methylureido)-phenyl N-o-methylphenyl carbamate weeks it was observed that the new active ingredients have a semisolid substance stronger herbicidal action and are better tolerated by beet m-(methylureido)-phenylN-m-methylphenylcarbamate than active ingredient 1I. semisolid substance Active ingredient I II III IV V VI VII VIII IX X X1 XII Crop plants:

Barley 0 10 0 0-10 '10 10 10 10-20 10 10-20 10 10-20 Wheat 0 10-20 0 10 10 0-10 10 10 10 10 0-10 10 Indian corn 0 0-10 0-10 10 0-10 10 10 0-10 0-10 10 10 10 est .5 0-10 30 10 -30 10 20-30 20 20-30 20 30 20 20-30 Unwanted plants:

' w dmustard 90-100 80-90 90-100 90-100 90 90-100 90 00 00-100 90 00-100 White goosefoot 00-100 80 90-100 00-100 90 100 00-100 90-100 00 100 90-100 100 Small nettle 100 00-100 90-100 100 00-100 100 90-100 00-100 00-100 00-100 00-100 100 Barnyard grass 70-80 40-50 7030 70 60-70 70-80 70 so No'rE.0= No action; 100=complete kill.

EXAMPLE 2 An agricultural plot which was overgrown with wild mustard (Sinapis arvensis), white goosefoot (Chenopodium album), small nettle (Urtica urens), common chickweed (Stellaria media), gallant soldier (Galinsoga parviflora) and annual meadow grass (Poa annua) was treated when the weeds were 2 to 6 cm. high with m-(3,3-dimethylureido)- phenyl N-p-chlorophenyl carbamate (1) and, for comparison, with 2-chloro-4,6-bis(ethylamino)-s-triazine (11), each at a rate of 5 kg. per hectare dispersed in 500 liters of water. After 7 to 8 days it could be observed that compound I had a stronger herbicidal action than compound 11. After 4 to 5 weeks almost all the plants had completely withered.

The following compounds have the same biological action at] in examples 1 and 2:

m-( 3,3-dimethylureido)-phenyl N-phenyl carbamate m.p. 180 to 182 C. m-( 3,3-dimethylureido)-phenyl N-o-chlorophenyl carbamate m-( 3,3-dimethylureido)-phenyl N-o-methylphenyl carbamate m.p. 154 to 156 C. v m-(3,3-dimethy1ureido)-phenyl N-o-methoxyphenyl carbamate m-( 3-phenylureido)-phenyl N-o-methylphenyl carbamate m.p. 127 to 136 C.

m-( 3-phenylureido )-phenyl N-p-methylphenyl carbamate m.p. 206 to 210 C.

m-( 3-phenylureido)-phenyl N-m-methylphenyl carbamate semisolic substance What we claim is:

l. A substituted ureidophenyl phenyl carbamate having the formula R1 R: R1

l N-C-0 N-C-N ll. ll R Q o R 

2. m-(3,3-Dimethylureido)-phenyl N-p-chlorophenyl carbamate. 